Hi John The 6CW4 Nuvistor that I know is a metal/ceramic valve by RCA....maybe all at cross purposes !
Yours Clive Green CEO Quartzlock Q Gothic, Plymouth Road, Totnes, Devon. TQ9 5LH England : +44 (0) 1803 862 062 : +44 (0) 1803 867 962 : cgr...@quartzlock.com : www.quartzlock.com Skype: clive.green.skype Messenger: cgr...@quartzlock.com Registered office: Gothic, Plymouth Road, Totnes, Devon. TQ9 5LH England Registered in England Think Environment, print only if necessary. This is an e-mail from Quartzlock (UK) Limited, its contents (including all attachments) and any files transmitted with it are confidential and intended solely for the individual(s) to which it is addressed and may also be privileged. It may not be copied or printed by anyone other than the addressee and may not be disclosed or distributed in any way. If you have received this e-mail in error please inform Quartzlock (UK) Limited and delete it from your mailbox or any other storage devices. 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Opinions, conclusions and other information expressed in this message are not given or endorsed by Quartzlock (UK) Limited unless otherwise indicated by an authorised representative independent of this message. -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of time-nuts-requ...@febo.com Sent: 14 August 2009 18:40 To: time-nuts@febo.com Subject: time-nuts Digest, Vol 61, Issue 59 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than "Re: Contents of time-nuts digest..." Today's Topics: 1. Re: on the "E" 117As and 5087As (Pete Lancashire) 2. Re: time-nuts Digest, Vol 61, Issue 57 (Mark Sims) 3. Re: Difference in GPS antennas (Pete Lancashire) 4. Difference in GPS antennas (Mark Sims) 5. Re: Difference in GPS antennas (Lux, Jim (337C)) 6. Taking apart timing GPS antenna (John Green) 7. Re: Difference in GPS antennas (Robert Darlington) 8. Re: Difference in GPS antennas (Dick Moore) 9. Best way for generating 8994.03 MHz from 2899.00042272.....MHz? (Javier Serrano) ---------------------------------------------------------------------- Message: 1 Date: Fri, 14 Aug 2009 09:38:21 -0700 From: "Pete Lancashire" <p...@petelancashire.com> Subject: Re: [time-nuts] on the "E" 117As and 5087As To: j...@quik.com, "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Message-ID: <5c603f05cff512b813d32e7bac6b71d0.squir...@petelancashire.com> Content-Type: text/plain;charset=iso-8859-1 I guess I have been lucky, I came across about 6 rolls a few years ago. I was picking up an instrument I won locally and as usual I took the time to find the drop boxs/dumpsters. They along with some other 'trash' such as the SMA terminators, attenuators, etc were ready to be tossed. To them not enough to make up a EBay lot. Another place is from old Ampprobes recorders, the problem there is the printed scale will be wrong. Before I found my HP rolls I get those from a local electrical disti who just gave them to me. They were in cubic feet per minute :-) -pete > Does anyone know of a source fot te 117A strip chart paper or the two > Nuvistors in the active loop? > > Thanks, > -John > > =============== > > >> Just passing on the info, no association etc >> >> 110421524421 3 ea 5087A's $500 or Make offer >> I'm making my own after I get my TBolt in a chassis >> >> 110424016673 2 ea 117A's $200 or Make offer >> I all ready have one >> >> -pete > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ------------------------------ Message: 2 Date: Fri, 14 Aug 2009 16:33:26 +0000 From: Mark Sims <hol...@hotmail.com> Subject: Re: [time-nuts] time-nuts Digest, Vol 61, Issue 57 To: <time-nuts@febo.com> Message-ID: <blu125-w20f4bcfe56e6ef9cd4a94bce...@phx.gbl> Content-Type: text/plain; charset="iso-8859-1" There is a Leica L1 only survey antenna on Ebay right now for $200 (220451355177) a Javad choke ring unit for $900 (200373329570). The listings don't have any specs on the operating voltage. These are typical prices for what these devices sell for (not a bargain, not a total rip). A little patience and shopping around and you could do better. A Sokkia L1/L2 antenna just sold for $350. One issue with them is that survey antennas are usually flat and timing antennas are conical (to shed snow and ice). If you live up north it could be an issue... ---------------------------------------- Thanks guys. I bookmarked that site. I don't know that I'll be able to find one but at least I know what to look for now. _________________________________________________________________ Get your vacation photos on your phone! http://windowsliveformobile.com/en-us/photos/default.aspx?&OCID=0809TL-HM ------------------------------ Message: 3 Date: Fri, 14 Aug 2009 09:46:32 -0700 From: "Pete Lancashire" <p...@petelancashire.com> Subject: Re: [time-nuts] Difference in GPS antennas To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Message-ID: <211166fe803baa2594d42ead9debdf15.squir...@petelancashire.com> Content-Type: text/plain;charset=iso-8859-1 I have some (well a LOT) of microwave absorber. it looks like a mix of ferrite and rubber that has been bonded to a stainless steel cloth (think window screening) in the middle. About 1/8" thick. I can get the make, p/n and a picture this weekend if interested. I remember the company that made it got bought out, which then got bought out etc and I gave up. Price would be free+shipping, there are about 400 each sheets about 30x30 inches. Each sheet must weight 5 lbs. > > > On 8/14/09 9:13 AM, "Mark Sims" <hol...@hotmail.com> wrote: > >> > >> >> Some of the data collection runs that I want to do is with the patch >> mounted >> on a pizza pan and in a cake pan and see if that helps the performance >> by >> faking what a survey antenna does. >> > > If you can scrounge up some suitable RF absorbing material to put on the > pan, that might be an interesting experiment. Maybe even something like > charcoal briquettes (I don't know if the resistivity is right..) > > > > I've tried the pizza pan thing, but that was because my antenna was a > magmount, and it was convenient. I didn't see if it gave better > performance. > A flat plate might actually be worse than putting the bare antenna up on a > pole, because it gives strong multipath from a very close reflection > point. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ------------------------------ Message: 4 Date: Fri, 14 Aug 2009 16:38:51 +0000 From: Mark Sims <hol...@hotmail.com> Subject: [time-nuts] Difference in GPS antennas To: <time-nuts@febo.com> Message-ID: <blu125-w184ee189ffb2c0177a791ece...@phx.gbl> Content-Type: text/plain; charset="Windows-1252" I have lots of carbon fiber cloth here (both woven and anisotropic mat). I know from past experience that it makes a pretty good RF absorber. I can put a tracking transmitter inside an all metal rocket and still get a good signal. Put it a a cardboard tube laminated with carbon fiber and the signal just about disappears. ---------------------------------------- If you can scrounge up some suitable RF absorbing material to put on the pan, that might be an interesting experiment. Maybe even something like charcoal briquettes (I don't know if the resistivity is right..) _________________________________________________________________ Windows Live?: Keep your life in sync. http://windowslive.com/explore?ocid=PID23384::T:WLMTAGL:ON:WL:en-US:NF_BR_sync:082009 ------------------------------ Message: 5 Date: Fri, 14 Aug 2009 09:45:48 -0700 From: "Lux, Jim (337C)" <james.p....@jpl.nasa.gov> Subject: Re: [time-nuts] Difference in GPS antennas To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Message-ID: <c6aae2cc.9bec%james.p....@jpl.nasa.gov> Content-Type: text/plain; charset="iso-8859-1" That?s probably exactly what you want (as opposed to the foamy stuff like in anechoic chambers). Very lossy for the magnetic field, typically, and you use it to suppress surface waves. On 8/14/09 9:46 AM, "Pete Lancashire" <p...@petelancashire.com> wrote: > I have some (well a LOT) of microwave absorber. it looks > like a mix of ferrite and rubber that has been bonded > to a stainless steel cloth (think window screening) in the > middle. About 1/8" thick. ------------------------------ Message: 6 Date: Fri, 14 Aug 2009 11:56:50 -0500 From: John Green <wpxs...@gmail.com> Subject: [time-nuts] Taking apart timing GPS antenna To: time-nuts@febo.com Message-ID: <abec162c0908140956i6608f15ei3627f724a3fcd...@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Hal Murray wrote: How did you get it apart? The Motorola/Andrew antenna that I have has screws. Best I remember, I just removed them and yanked the top off. I do believe there was a seal that had to be overcome. ------------------------------ Message: 7 Date: Fri, 14 Aug 2009 11:05:34 -0600 From: Robert Darlington <rdarling...@gmail.com> Subject: Re: [time-nuts] Difference in GPS antennas To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Message-ID: <b3bd5fcb0908141005r5071ece0j4c5e410254fa6...@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Hrm, I'm looking for a sheet of Eccosorb to make an anechoic chamber (a very small one) for testing 2.4GHz printed (PCB) antennas. I'd be interested in knowing the specs. The idea with what I'm doing is that I can sweep the antenna with the network analyzer and still be near the antenna to keep the cables short, while at the same time not interfere with the measurements. I met a guy from Microchip last week that showed me what he was doing and what works well for him. He built a box about 8" high and about 5 inch square on the bottom (inside dimensions). Even though it's pretty parallel on the inside, reflection is a minimum because of the material. -Bob On Fri, Aug 14, 2009 at 10:46 AM, Pete Lancashire <p...@petelancashire.com>wrote: > I have some (well a LOT) of microwave absorber. it looks > like a mix of ferrite and rubber that has been bonded > to a stainless steel cloth (think window screening) in the > middle. About 1/8" thick. > > I can get the make, p/n and a picture this weekend if interested. > I remember the company that made it got bought out, which then > got bought out etc and I gave up. > > Price would be free+shipping, there are about 400 each > sheets about 30x30 inches. Each sheet must weight 5 lbs. > > > > > > > > On 8/14/09 9:13 AM, "Mark Sims" <hol...@hotmail.com> wrote: > > > >> > > > >> > >> Some of the data collection runs that I want to do is with the patch > >> mounted > >> on a pizza pan and in a cake pan and see if that helps the performance > >> by > >> faking what a survey antenna does. > >> > > > > If you can scrounge up some suitable RF absorbing material to put on the > > pan, that might be an interesting experiment. Maybe even something like > > charcoal briquettes (I don't know if the resistivity is right..) > > > > > > > > I've tried the pizza pan thing, but that was because my antenna was a > > magmount, and it was convenient. I didn't see if it gave better > > performance. > > A flat plate might actually be worse than putting the bare antenna up on > a > > pole, because it gives strong multipath from a very close reflection > > point. > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ------------------------------ Message: 8 Date: Fri, 14 Aug 2009 10:22:54 -0700 From: Dick Moore <rich...@hughes.net> Subject: Re: [time-nuts] Difference in GPS antennas To: time-nuts@febo.com Message-ID: <21a62fcd-5e85-447c-8d2d-a305f0318...@hughes.net> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes On Aug 14, 2009, at 9:27 AM, time-nuts-requ...@febo.com wrote: Maybe why choke rings are rings. > > > Message: 9 > Date: Fri, 14 Aug 2009 09:27:52 -0700 > From: "Lux, Jim (337C)" <james.p....@jpl.nasa.gov> > Subject: Re: [time-nuts] Difference in GPS antennas > To: Discussion of precise time and frequency measurement > <time-nuts@febo.com> > Message-ID: <c6aade98.9be6%james.p....@jpl.nasa.gov> > Content-Type: text/plain; charset="iso-8859-1" > > clip>>>> > I've tried the pizza pan thing, but that was because my antenna was a > magmount, and it was convenient. I didn't see if it gave better > performance. > A flat plate might actually be worse than putting the bare antenna > up on a > pole, because it gives strong multipath from a very close reflection > point. ------------------------------ Message: 9 Date: Fri, 14 Aug 2009 19:39:46 +0200 From: Javier Serrano <javier.serrano.par...@gmail.com> Subject: [time-nuts] Best way for generating 8994.03 MHz from 2899.00042272.....MHz? To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Message-ID: <83e48fa10908141039i3c3a3116ue54c9e364b46c...@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Dear nuts, A colleague from a Free Electron Laser lab has the following problem: he needs to make a frequency to use as an X-band LO that is *exactly*8994.03 MHz (3*2998.01 MHz) and it *must* be locked to his S-band LO which is exactly 2998.01*732/757 MHz (2899.00042272.....MHz). He intends to multiply his S-LO by 3 and that gets him close, about 297 MHz away. Then he can add another frequency he has(that is locked to his S-LO) of 241.6..... MHz (2998.01*61/757 MHz to be exact) and that brings him to about 55 MHz. To generate that 55 MHz he has several options: - Cascading two DDS chips to get many bits of frequency resolution and leave the thing in open loop. I don't like the absence of feedback in this option, and I have never cascaded DDS chips to achieve an increase in frequency resolution, although on paper there seems to be no problem. The increase in accuracy would be such that even in open loop it would take a very very long time to go out of spec (his spec is 0.01 degrees at X-band, during a whole year). This time would be long enough for him not to care about it. - Generating it using a standard PLL with some kind of good quality VCO. He is concerned by the required VCO quality in this case. - Combining the two above, i.e. using the DDS as a VCO by controlling its Frequency Tuning Word, but in a closed loop configuration. Has anybody out there been confronted to a similar problem? Many thanks in advance, Javier ------------------------------ _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts End of time-nuts Digest, Vol 61, Issue 59 ***************************************** _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
